Field of the Invention
The present invention relates to a method for controlling a plurality of protocols and a plurality of application contexts in a distributed system connected through a communication network, and more particularly to a method for efficiently establishing a connecting line from a user application to a plurality of distributed database systems.
When a communication path is to be established from a system which executes a user application to distributed databases, it is performed by using a predetermined protocol. Detailed specification of the protocol is defined by an application context. The application context is defined by a standard such as ISO and a communication path may not be established if the application context does not match even if the protocol matches.
In the past, in establishing a communication path from a system which executes an application program, communication with a destination system may be done by the application program which uses an already established logical communication path by communication path allocating means, as disclosed in JP-A-4-23155. Since the number of times of establishment/release of the communication path by communicating with the destination system by using the already established communication path, a communication fee in a packet transmission system can be reduced.
In the prior art, the communication path, the communication protocol to be used and the application context are preestablished, and no attention is paid for the use of a plurality of protocols or application contexts by one application program.
When the application program uses a plurality of protocols or application contexts, it is necessary to program by the application program to permit the use of a plurality of communication control programs but it is not easy to modify the protocols and the application contexts.